Objective:
1) Assess genetic diversity and pathogenicity of curly top virus species/strains; 2) Survey weed populations to determine incidence of major curtovirus species and strains that may serve as wild reservoirs for movement of virus into crops.

Approach:
Plant samples will be shipped to ARS, nucleic acid extracted and examined for virus species by PCR and sequencing. Symptom severity will be analyzed, and competitiveness of new viruses variants with traditional isolates will be explored in select hosts through greenhouse testing.